This work may not be copied, distributed, displayed, published, reproduced, transmitted, modified, posted, sold, licensed, or used for commercial purposes. By downloading this file, you are agreeing to the publisher’s Terms & Conditions.

Letter to the Editor

Delusional Infestation With Black Mold Presenting to the General Hospital

Alan S. Lewis, MD, PhD, and Mark A. Oldham, MD

Published: April 9, 2015

Delusional Infestation With Black Mold Presenting to the General Hospital

To the Editors: Delusional infestation is defined by fixed, false beliefs of infestation with parasites or inanimate objects. Patients typically present to clinicians in primary care and dermatology rather than to mental health practitioners.1 To our knowledge, this is the first reported case of delusional infestation associated with "black mold." Further, it is a rare case with systemic involvement and of fungus-related delusional infestation.


Case report. Mr A, a divorced 54-year-old homeless white man, was transferred to our hospital’s medicine service for videoelectroencephalography (vEEG) after experiencing seizures at another hospital. He reported taking more than 20 mg of lorazepam daily, explaining that lorazepam treated the "neurotoxic" effects of a "black mold infection" he acquired over 1 year ago, and his lorazepam supply had run out 2 days prior to presentation. He attributed numerous somatic symptoms to the black mold, or Stachybotrys chartarum, infection including tinnitus, fatigue, and headaches. Mr A was a limited historian and declined to identify collateral sources but alluded to multiple inpatient psychiatric and substance admissions. Pertinent medical history was limited to a head injury as an adolescent. Mental status examination revealed an unkempt, agitated man with forceful speech, intense and labile affect, and obsessive thoughts with moderate paranoia. His thoughts were perseverative and overinclusive but generally linear and goal-directed. He denied hallucinations or suicidal or homicidal ideation.

No seizure activity was seen on the vEEG, and a comprehensive physical, laboratory, and neuroimaging workup did not reveal evidence of fungal infection or another cause for his reported symptoms. Neuroleptics and mood stabilizers were recommended for psychosis and mood elevation but were persistently refused. A slow lorazepam taper was accompanied by episodes of rhythmic shaking and agitation at doses below 8 mg daily. Repeated EEGs during these episodes were unrevealing, substantiating a diagnosis of nonepileptic seizures. Mr A was dissatisfied with the taper and ultimately discharged against medical advice after undergoing a risk assessment and capacity evaluation. He refused treatment referral.


Delusional infestation principally involves the skin, and almost all reported cases with fungus include dermatologic manifestations. We conducted a literature search using MEDLINE, EMBASE, and PsycINFO using terms related to delusions (psychosis, psychotic, delusion*, delusory, Ekbom*, parasitophobi*, and Morgellon*) with those related to fungus/black mold (mold*, fungus, fungal, mycotoxi*, and Stachybotrys).2-6 Table 1 provides a summary of the cases found.

Table 1

Click figure to enlarge

This is a rare report of delusional infestation with systemic symptoms and, to our knowledge, the first reported case of black mold delusional infestation. Whereas a controversial study suggests that mycotoxins may cause vague neurologic illness,7 our patient’s limited mold exposure more than 1 year prior to presentation with persistent symptoms is inconsistent with even that report. Severe benzodiazepine use disorder was evident. A clear understanding of Mr A’s psychosis was hindered by lack of collateral history. No secondary cause was identified, so our differential diagnosis included schizophrenia, schizoaffective disorder, bipolar disorder, or obsessive-compulsive disorder with absent insight.3 Conversion disorder, factitious disorder, and malingering were also considered given the vEEG results. Detailed discussion of managing delusional infestation has been reviewed elsewhere.8-10 Management should include medical workup to rule out secondary causes. First-line treatment for primary delusional infestation includes antipsychotic medication. Both first-generation10 and second-generation9 agents have been used successfully. Attention should be given to common comorbid disorders such as depression and anxiety.11 Mental health referral is recommended.

Patients with delusional infestation suffer substantially from psychosocial dysfunction and are at increased risk for harm from hazardous treatments, as exemplified by our patient using high-dose benzodiazepines. As with this case, most patients with delusional infestation present to nonpsychiatric physicians, thus an understanding of diagnosis, workup, and treatment approaches is critical to limit unwarranted medical intervention and promote functional recovery.


1. Foster AA, Hylwa SA, Bury JE, et al. Delusional infestation: clinical presentation in 147 patients seen at Mayo Clinic. J Am Acad Dermatol. 2012;67(4):673.e1-e10. PubMed doi:10.1016/j.jaad.2011.12.012

2. Sugahara H, Otani Y, Sakamoto M. Delusional parasitosis accompanied by word deafness due to cerebral infarction: folie í  deux. Psychosomatics. 2000;41(5):447-448. PubMed doi:10.1176/appi.psy.41.5.447

3. Khalili B, Montanaro MT, Bardana EJ Jr. Inhalational mold toxicity: fact or fiction? a clinical review of 50 cases. Ann Allergy Asthma Immunol. 2005;95(3):239-246. PubMed doi:10.1016/S1081-1206(10)61220-3

4. Geddes ER, Rashid RM. Delusional tinea: a novel subtype of delusional parasitosis. Dermatol Online J. 2008;14(12):16. PubMed

5. Narang T, Singh SM, Kavita. Delusional infestation with fungus. Indian J Dermatol Venereol Leprol. 2012;78(5):645-646. PubMed doi:10.4103/0378-6323.100590

6. Fisher MA, Campbell J, Cervantes L, et al. Doctor’s dilemma: differentiating between reality and delusion in a psychotic physician. 35th Annual Meeting of the Society of General Internal Medicine; May 2-12, 2012; Orlando, FL.

7. Shoemaker RC, House DE. Sick building syndrome (SBS) and exposure to water-damaged buildings: time series study, clinical trial and mechanisms. Neurotoxicol Teratol. 2006;28(5):573-588. PubMed doi:10.1016/

8. Lepping P, Freudenmann RW. Delusional parasitosis: a new pathway for diagnosis and treatment. Clin Exp Dermatol. 2008;33(2):113-117. PubMed doi:10.1111/j.1365-2230.2007.02635.x

9. Freudenmann RW, Lepping P. Second-generation antipsychotics in primary and secondary delusional parasitosis: outcome and efficacy. J Clin Psychopharmacol. 2008;28(5):500-508. PubMed doi:10.1097/JCP.0b013e318185e774

10. Lepping P, Russell I, Freudenmann RW. Antipsychotic treatment of primary delusional parasitosis: systematic review. Br J Psychiatry. 2007;191(3):198-205. PubMed doi:10.1192/bjp.bp.106.029660

11. Hylwa SA, Foster AA, Bury JE, et al. Delusional infestation is typically comorbid with other psychiatric diagnoses: review of 54 patients receiving psychiatric evaluation at Mayo Clinic. Psychosomatics. 2012;53(3):258-265. PubMed doi:10.1016/j.psym.2011.11.003

Alan S. Lewis, MD, PhD

Mark A. Oldham, MD

Author affiliations: Department of Psychiatry, Yale University School of Medicine (both authors) and Psychological Medicine Service, Yale-New Haven Hospital (Dr Oldham), New Haven, Connecticut.

Potential conflicts of interest: None reported.

Funding/support: This work was funded in part by National Institute of Mental Health grant T32MH014276 (A.S.L.).

Role of the sponsor: The sponsor provided support for preparation of the manuscript.

Acknowledgments: The authors thank Jorge Aguilar-Zanatta, MD (Danbury Hospital, Danbury, Connecticut), Paul Desan, MD, PhD (Department of Psychiatry, Yale University, New Haven, Connecticut), and Kimberly Yonkers, MD (Department of Psychiatry, Yale University, New Haven, Connecticut) for formative comments on the manuscript. Drs Aguilar-Zanatta, Desan, and Yonkers report no conflicts of interest related to the subject of this article.

Published online: April 9, 2015.

Related Articles

Volume: 17

Quick Links:


Buy this Article as a PDF